Integral and lenticular imaging have been proposed and practiced since the beginning of the 20th Century, notably by Lippman, Ives, and others, culminating in 1950 with the work of Victor Anderson, who made lenticular imaging practical and commercialized it. Since then, there has been no fundamental change in the way lenticular images work.
The basic practice has been to select two or more individual images that relate to one another in some way (different views of a 3D scene, different frames of a movie, video, or animation, or just different images on a chosen topic such as a product and its price, before and after pictures, or other images the creator of the picture wants the viewer to see), and to partition the selected individual images into multiple image slices. The image slices, which may be vertical or horizontal slices, are then reassembled back together into one composite image, which is displayed on an image medium providing a viewing surface containing data from each of the individual images. This image medium is overlaid with an image-directing device, e.g. a lenticular screen.
There are two conventional types of image-directing devices, for the purpose of this invention. One type comprises a pattern of vertically- or horizontally-oriented opaque elements, referred to as a barrier screen. Another type of image-directing device comprises an array of cylindrical micro-lenses. This array of cylindrical micro-lenses is referred to as a lenticular screen. The effect of the image-directing device is to make the individual images, which were assembled into the composite image, visible individually, each from a different viewing position.
The use of tilted lenticular lenses has been proposed and implemented in the past for other functions. In U.S. Pat. No. 3,409,351, D. F. Winnek disclosed a methodology for recording a lenticular 3D image in two steps. First a negative is recorded in a camera through a lenticular lens. The individual strip-images recorded behind each of the lenticular lenses are reversed upon passage through the lenticular lens elements. Due to this reversal, viewing the 3D negative provides a pseudoscopic image, wherein depth is reversed. Then, using a projection arrangement similar to that used when enlarging a negative to make a conventional print, the lenticular negative is projected through another lenticular lens onto photographic print material to make a final 3D print. This step allows the final image to be larger, smaller, or the same size as the lenticular negative, as desired, while reversing the strip-images once again to produce an orthoscopic 3D print. The problem created by projecting an image with an inherent vertical line pattern (due to the structure of the first lenticular lens) through another vertical line pattern (the second lenticular lens) is the creation of a noticeable moire pattern. To diminish or visibly eliminate the appearance of this moire pattern, Winnek suggests providing an angle between the axes of the two lenticular lenses. He determines that the angle between the two lenses should be less than 20 degrees to prevent vignetting of the images in the corners.
Use of tilted lenticulars has also been proposed in U.S. Pat. No. 6,373,637 by S. Gullick, Jr. and R. Taylor. This patent teaches the user to take two or more images, rotate them to a tilt angle with respect to the vertical, digitize and multiplex the images vertically, attach them to either a lenticular or a “herringbone lenticular” lens oriented vertically, and then rotate the finished product so that the image is once again vertically oriented, leaving the lenses tilted at the image-tilt-angle minus ninety degrees. Finally, the user is to trim the tilted lens, discarding the unused portions as waste, so that two of its sides are vertical, with the other two sides being horizontal. The technique is proposed so that rotating the finished lenticular about a vertical axis provides a stereoscopic 3D view with parallax, while rotating the finished lenticular about a horizontal axis provides a moving image.
The inventor believes that the prior art nevertheless fails to disclose or suggest means for the production of a composite image display that produces the same perceived effect with various viewing orientations, i.e. whether it is tipped vertically or horizontally, such as is taught herein, nor the methodology to form such a composite image which works with a tilted lenticular or barrier screen, as taught herein, nor the methods of making tilted lenticular lenses or barrier screens, which are also taught herein.